Manufacturing Technology Journal, 2013 (vol. 13), issue 1
Study of advanced Ni - base ŽS6K alloy by quantitative metallography methods
Juraj Belan
Manufacturing Technology 2013, 13(1):2-7 | DOI: 10.21062/ujep/x.2013/a/1213-2489/MT/13/1/2 
The aerospace industry is one of the biggest consumers of advanced materials because of its unique combination of mechanical and physical properties and chemical stability. Highly alloyed stainless steel, titanium alloys and nickel based superalloys are mostly used for aerospace applications. High alloyed stainless steel is used for the shafts of aero engine turbines, titanium alloys for compressor blades and finally nickel base superalloys are used for the most stressed parts of the jet engine - the turbine blades. Nickel base superalloys were used in various structural modifications: as cast polycrystalline, a directionally solidified, single crystal...
Influencing the crystallization of secondary alloy AlSi6Cu4 with strontium
Dana Bolibruchová, Marek Brůna
Manufacturing Technology 2013, 13(1):7-14 | DOI: 10.21062/ujep/x.2013/a/1213-2489/MT/13/1/7
This work deals with modification of aluminum alloy AlSi6Cu4 with strontium in graduated amounts. Submited article examines modification influence on the mechanical properties such as tensile strength (Rm), elongation (A5) and Brinell hardness (HBW). Article also includes analysis of alloy microstructure modified by strontium and analyzes the impact of strontium on the gas content of the melt. This work deals with finding the optimal amount of strontium to achieve changes in the shape of the coarse eutectic silicon plates to fine rounded AlSi6Cu4 alloy rods. Durin experiment was found, that optimum amount of the used modifier with respect to the mechanical...
Study of the gas content in aluminum alloys
Dana Bolibruchová, Lukáš Richtárech
Manufacturing Technology 2013, 13(1):14-20 | DOI: 10.21062/ujep/x.2013/a/1213-2489/MT/13/1/14
This article deals with the gas content of aluminum alloys and prediction of gas content using the foundry simulation software. In the theoretical section summarizes the main causes of gas content of aluminum alloys, the effects of modifications and inoculation, as the survey gas content and the possibility of using simulation software for predicting the gas content. The experimental part is tested for gas content f the test castings and verificated by simulation program ProCAST. As an experimental alloy was used AlSi7Mg0,3. The specimens were evaluated using four methods: microscopically, macroscopically, using a stereomicroscope and by evaluating...
The Simulation of Influence of Quenching Temperature on Properties of Bearing Rings
Martin Brezničan, Peter Fabian, Jozef Meško, Mário Drbúl
Manufacturing Technology 2013, 13(1):20-25 | DOI: 10.21062/ujep/x.2013/a/1213-2489/MT/13/1/20
Roller bearings are a very important part of modern machineries and equipments. They have a significant impact on the smooth running, reliable performance and durability. Replacing worn or damaged roller bearings often require extensive disassembly of the machine and the costs often exceed the price of the replaced bearings. There is an influence of the correct bearing construction and dimensional accuracy on the durability, but the grade and quality of used steel and its heat treatment are very important, too. Tempering is an important chapter. Tempering has the effect to modifying the properties of martensite after quenching and transformation of...
Complex evaluation of porosity in A356 aluminium alloy using advanced porosity module
Marek Brůna, Lukáš Kucharčík, Augustín Sládek
Manufacturing Technology 2013, 13(1):26-30 | DOI: 10.21062/ujep/x.2013/a/1213-2489/MT/13/1/26
In this work, the formation of porosity (micro, macro porosity and pipe shrinkage) has been examined under different casting conditions aimed at manipulating cooling rate and pouring temperature of aluminium alloy A356. The results of the experiment will attempt to verify that the solidification rate and pouring temperature have an effect on the formation and character of gas pores in castings from A356 alloy. For this purposes was used advanced porosity module integrated into simulation software ProCAST. Specific casting and mold was designed to be able observe porosity formation. Main aim was to choose the right shape, so all types of porosity occur...
Influence of repeated remelting of the alloy RR.350 on structure and thermo-mechanical properties
Marek Břuska, Petr Lichý, Michal Cagala, Jaroslav Beňo
Manufacturing Technology 2013, 13(1):31-35 | DOI: 10.21062/ujep/x.2013/a/1213-2489/MT/13/1/31
This research investigates the influence of repeated use of the Al-Cu-based alloy. In our case we used the alloy RR.350. Specimens for the tensile test were cast into a metallic mould, to which a protective coating was applied. Altogether 15 specimens were prepared from each melt in order to obtain more accurate results. During casting the temperature of metal and mould was controlled from the viewpoint of ensuring constant conditions of the experiment. Test bars were prepared from the cast specimens for measurement of tensile strength at normal (20°C) and elevated temperatures (up to 350°C). Furthermore parts were taken from the cast specimens for...
Influence of returning material on porosity of die castings
Ľubomír Eperješi, Jozef Malik, Štefan Eperješi, Daniel Fecko
Manufacturing Technology 2013, 13(1):36-39 | DOI: 10.21062/ujep/x.2013/a/1213-2489/MT/13/1/36
With increasing tendency of die castings production, also the possibility to produce castings with maximum usage of molten metal grows. Residual of non-used molten metal, e.g. sprues, feeders, splashes and saw-dusts are used in next production as returning material. With returning material a lot of non-suitable elements is brought into the melting process, but with decreasing of input costs it creates inseparable part of production process. Usage of returning material in melt production has negative influence on final quality of produced castings, because of bringing of inheritable properties into produced melt. Important factor in melt production...
Using of Thermal Analysis in the Industrial Practice - Consumption Reduction of Grain-Refinement Master Alloy and Optimization of Computer Simulation Results
Marko Grzincic, Mile Djurdjevic, Florian Dirnberger
Manufacturing Technology 2013, 13(1):39-43 | DOI: 10.21062/ujep/x.2013/a/1213-2489/MT/13/1/39
The solidification process of a metal or alloy is accompanied by the evolution of heat the magnitude of which depends on the various phases that form during the solidification. Recorded temperature-time data can yield quantitative information about the alloy solidification process. Such a plot is called a cooling curve and the general name given to the technique is thermal analysis. The cooling curve serves as a "finger print" of the solidification process and can be used to predict the structure of the test sample and consequently the actual casting. The aim of this paper is to show the ability of the thermal analysis technique in order to predict...
Elimination of the negative effect of Fe-rich intermetallic phases in secondary (recycled) aluminium cast alloy
Lenka Hurtalová, Eva Tillová
Manufacturing Technology 2013, 13(1):44-50 | DOI: 10.21062/ujep/x.2013/a/1213-2489/MT/13/1/44
Improved mechanical properties of secondary alloys are strongly dependent upon the morphologies, type and distribution of the second phases, which are in turn a function of alloy composition and cooling rate. In Al-Si-Cu type alloys, however, Fe showed to have the most detrimental effect on ductility of all of the common impurities. Iron impurities can either come from the original bauxite ore or be acquired during subsequent melting, remelting and casting, e.g. by contamination from the melting pot etc. The shape of iron compounds is more influential than the quantity of those iron compounds. Therefore was used heat treatment of experimental material...
Impact Analysis of Mutual Rotation of Roller Bearing Rings on the Process of Contact Stresses in Rolling Elements
Lenka Jakubovičová, Milan Sága, Milan Vaško
Manufacturing Technology 2013, 13(1):50-54 | DOI: 10.21062/ujep/x.2013/a/1213-2489/MT/13/1/50
Purpose of this paper is to present the magnitude of the impact of roller bearing rings mutual slewing to the process of contact stresses in rolling elements. The roller bearing satisfies prescribed basic static load rating if it is loaded by the maximum specified load only in the radial direction according to the ISO/TS 16281. However, the real roller bearings are not loaded only in the radial direction in practice. During operation there is mutual slewing of the bearing roller rings. This leads to a change in the conditions of contact and to a change in contact stresses. Stress state will be evaluated in the most loaded element of the roller bearing....
Experimental evaluation of the new lance for powder injection
Jan Jezierski, Krzysztof Janerka
Manufacturing Technology 2013, 13(1):55-59 | DOI: 10.21062/ujep/x.2013/a/1213-2489/MT/13/1/55
The paper presents the results of the evaluation experiments of the new lance for powder injection process. The pneumatic powder injection process itself has been well known since many years and it can be operated both with submerged and non-submerged lance. The new invented by authors injection lance is dedicated for processes without its submersion especially when the powders are injected into liquid metal bath inside the ladles or induction crucible furnaces. In these cases it is important to not introduce the carrier gas into metal volume to make the temperature decrease as low as possible. However, when the lance is not submerged the problem with...
In-phase multiaxial fatigue experimental analysis of welded cylindrical 6063-T66 aluminium alloy specimens
Peter Kopas, Milan Sága
Manufacturing Technology 2013, 13(1):59-64 | DOI: 10.21062/ujep/x.2013/a/1213-2489/MT/13/1/59
This paper is concerned with an experimental and numerical study of the fatigue behaviour of cylindrical 6063-T66 welded specimens subjected to biaxial loading. In-phase torsion-bending fatigue tests under constant amplitude loading were performed in a standard electromechanical machine with a suitable gripping system. The experimental part was focused on the modeling of combined biaxial loading and determining the number of cycles to fracture in the region of low-cycle fatigue. In-phase loading can be treated fairly well using the conventional hypotheses (von Mises or Tresca) on basis of the nominal, structural or local strains or stresses. Based...
Inoculant Addition Effect on Thermomechanical and Thermophysical Properties of Mg-Sr Magnesium Alloy
Petr Lichý, Jaroslav Beňo, Michal Cagala
Manufacturing Technology 2013, 13(1):64-67 | DOI: 10.21062/ujep/x.2013/a/1213-2489/MT/13/1/64
Satisfactory tensile properties, even at elevated temperatures, are very important for thermally stressed parts in car structures (e.g. cylinder heads and engine blocks). This condition is satisfied also by magnesium-based alloys containing strontium and rare earth metals, which are very expensive, though. The presented paper deals with study of Mg-Sr-type magnesium alloy. To be specific, this is AJ62 alloy which belongs among developmentally new magnesium-based alloys. This alloy combines very good castability and heat resistance, moreover, this is cost-effectively available material. This paper is focused on this alloy structure refinement. Analysis...
Modified hydrated sodium silicate as a modern binder for ecological moulding sands
Katarzyna Major-Gabryś, Stanisław M. Dobosz, Jarosław Jakubski
Manufacturing Technology 2013, 13(1):68-73 | DOI: 10.21062/ujep/x.2013/a/1213-2489/MT/13/1/68
This article is devoted to ecological moulding sands with hydrated sodium silicate as binder. The inorganic nature of the binder results in poor knock-out properties and low ability to mechanical reclamation of tested moulding sands. In the present study authors focused on developing a new addition to the composition of these environmental friendly foundry moulding sands, providing them better knock-out properties. The analysis of the literature data let authors focus on the use of additives containing Al2O3 as components of moulding sands with hydrated sodium silicate. These additives provide better knock-out properties of moulding sands measured...
Squeeze casting results of aluminium alloys
Iva Nová, Jiří Machuta
Manufacturing Technology 2013, 13(1):73-79 | DOI: 10.21062/ujep/x.2013/a/1213-2489/MT/13/1/73
The paper deals with a squeeze casting process. This process added a new knowledge in to research in the branch by crystallization of aluminium alloys. Due to this purpose there was designed a special tool, which was placed on hydraulic press. The squeeze casting was carried out on an aluminium alloy (AlSi12, with 12 % silicon). The main aim was study of the aluminium alloy structure, which was established at a pressure of crystallizing melt. In this way of the material crystallization was produced a truncated cone part with the larger the base (∅ 100 mm x 105 mm). The structure of specimens was monitored on a light microscope and was evaluated...
Finite Element Implementation of Multi-Pass Fillet Weld with Phase Changes
Pavol Novák, Jozef Meško, Milan Žmindák
Manufacturing Technology 2013, 13(1):79-85 | DOI: 10.21062/ujep/x.2013/a/1213-2489/MT/13/1/79
First, in this paper, a brief review of theoretical aspects of weld simulation and residual stress modelling using the finite element method (FEM) is presented. Thermo-elastic-plastic formulations using a von Mises yield criterion with nonlinear isotropic hardening has been employed. Residual stresses obtained from the analysis have been shown. The commercial FEM code ANSYS and a user created code were used for uncoupled thermal-mechanical analysis. Second, the aim of this paper is to compare ANSYS capabilities extended by authors to model weld phenomena versus well known SYSWELD code. Element birth and death FEM technique was used to simulate the...
Metallurgical and Material Properties of Castings Manufactured from Stainless Steel G-X4CrNi13-4 and G-X4CrNiCu13-4
Josef Odehnal, Stanislav Brotánek
Manufacturing Technology 2013, 13(1):85-91 | DOI: 10.21062/ujep/x.2013/a/1213-2489/MT/13/1/85
This article presents the metallurgical and material properties of castings from stainless steel G-X4CrNi13-4 and G-X4CrNiCu13-4, which can be obtained under the conditions of the Foundry shop of PILSEN STEEL s.r.o. The article mentions furnace units of primary and secondary metallurgy in which the stated quality steel is produced. By way of illustration of achieved properties of melt, the heat analyses and micro-purity of steel are shown. Mechanical properties of steel are represented in well arranged graphs showing achieved values of the yield point, tensile strength, and impact energy at various temperatures, such as for example: 20, -10, -20, -30,...
Effect of opening material granularity on the mould properties and the quality of castings made by patternless process technology
Richard Pastirčák, Emil Krivoš
Manufacturing Technology 2013, 13(1):92-97 | DOI: 10.21062/ujep/x.2013/a/1213-2489/MT/13/1/92
Submitted article deals with the methods to improve mould breathability when using the Patternless process method and also examines the influence of opening material grain size on the dimensional and shape precision of made castings. Mentioned methods are based on the principle of direct milling cavity into block from moulding mixture with CNC machining. As the moulding material was used CT moulding compound composed of opening materials SH 35, SH 31 and water glass as binder. The curing process took place by purging CO2 gas through moulding compound. To achieve the highest quality surface cavity was used protective coating PROTECT WC1. The final shape...
Temperature gradient in cooling down Fe-C-Cr alloy casting
Andrzej Studnicki, Jan Szajnar
Manufacturing Technology 2013, 13(1):98-103 | DOI: 10.21062/ujep/x.2013/a/1213-2489/MT/13/1/98
The fragment of investigations of primary crystallization process of casting made from chromium cast steel and chromium cast iron contain about 17% chromium was described in the article. The analysis of change in temperature gradient on cross-section of cooling model casting was introduced. To the investigations was applied TGDA (thermal gradient and derivative analysis) method worked out in the Department of Foundry in Silesian University of Technology in Gliwice which consists in multi-drop measurement of cooling temperature in casting using thermocouple locate on the direction of transferring warm from the casting to mould. On the basis of registered...
The zone without carbon in alloy layer obtained on steel cast
Jan Szajnar, Agnieszka Walasek, Czesław Baron
Manufacturing Technology 2013, 13(1):103-108 | DOI: 10.21062/ujep/x.2013/a/1213-2489/MT/13/1/103
In the submitted article are presented the results of researches on the steel cast with surface alloy layer in this article. The simulation of the disintegration of the elements in the place where two materials were in contact was done in order to observe the effects between them. The temperature, the thickness of the layer, micro hardness and the structure were thoroughly examined. The researches were conducted to examine the zone without carbon forming in the joint of two materials. The influence of pouring temperature, the thickness of the cast wall and the size of pad grain on the zone without carbon forming process were also examined. It was also...
The role of antimony in modifying of Al-Si-Cu cast alloy
Eva Tillová, Mária Farkašová, Mária Chalupová
Manufacturing Technology 2013, 13(1):109-114 | DOI: 10.21062/ujep/x.2013/a/1213-2489/MT/13/1/109
The microstructure evolution and the tensile strength changes of hypoeutectic AlSi6Cu4 cast alloy modified by AlSb10 (0 - 10 000 ppm) was systematically investigated. The samples were study without and after T6 heat treatment. Several types of etching were used, which includes standard black and white etching (0.5 % HF), colour etching by Weck-Al (for documentation the eutectic cells) and deep etching by HCl (for eutectic Si morphology study). The results show that the addition of Sb into AlSi6Cu4 cast alloy should act as a modifier, so it supposes to change the eutectic Si morphology. However, its effect as a modifier is not as significant as we have...
Influence of heat treatment on the microstructure of synthetic nodular cast irons
Alan Vaško
Manufacturing Technology 2013, 13(1):115-119 | DOI: 10.21062/ujep/x.2013/a/1213-2489/MT/13/1/115
The article deals with the influence of charge composition on the microstructure and mechanical properties of synthetic nodular cast irons after casting and after heat treatment (ferritizing annealing and isothermal heat treatment). The paper shows a comparison of the microstructure of nodular cast irons with the graded amount of steel scrap in a charge. The chemical composition of individual meltages was regulated alternatively by ferrosilicon (FeSi) and carburizer or metallurgical silicon carbide (SiC). The results of the experiments show that the SiC additive positively influences the microstructure as well as the mechanical properties of nodular...
Hardness of Ductile Cast Iron Castings and its Control in Praxis
Iveta Vasková, Peter Šebek, Igor Mulik
Manufacturing Technology 2013, 13(1):120-122 | DOI: 10.21062/ujep/x.2013/a/1213-2489/MT/13/1/120
Foundry is one of the oldest industry branch. In the evolution of humankind it played great role wih always improving mechanical properties of metals and in using of newest knowledges, it still plays one of the key function in all spheres of our lives. We meet everyday with the castings. It is the same if we sit in the car or we are eating the waffle. The production of every single casting needs individual approach for repeatidly achievement of desired material properties. Hardness is one of the basic property of metal materials in common. From hardness depends how easy, or how hard would be given material machined and what kind of materials, tools...
Assessment of the effect of temperature and annealing time homogenization AlCu4MgMn alloys in terms of microstructure image analysis methods and EDX
Viktorie Weiss, Ingrid Kvapilova
Manufacturing Technology 2013, 13(1):123-127 | DOI: 10.21062/ujep/x.2013/a/1213-2489/MT/13/1/123
Homogenization is defined as a method of heat treatment, which consists of holding time at high temperature near the liquidus (approx. 0.7 to 0.8 the melting temperature) to eliminate chemical inhomogeneity diffusion processes. Cause of segregation is selective crystal solidification in the gradual change in composition of the solid phase. Melt began to appear after certain of the hypothermia during cooling, and the growth of germs in accordance with the general laws of crystallization. Each rigid layer has a different chemical composition. The first part of the solid phase ingredient low concentration of the element last, on the contrary, very high....
The Efficiency of Different Types of Inoculation of Pure Al and AlSi2 Alloy
Tomasz Wróbel
Manufacturing Technology 2013, 13(1):127-133 | DOI: 10.21062/ujep/x.2013/a/1213-2489/MT/13/1/127
In paper problem concerning inoculation of primary structure of aluminum with purity of 99,5% and 99,8% and AlSi2 alloy, which is realized mainly by intensification of liquid metal movement in mould is presented. In aim of realization of forced movement during the crystallization of liquid metal was used rotating electromagnetic field produced by the induction coil supplied by current with elevated frequency. The degree of structure refinement was represented by equiaxed crystals zone content on transverse section of ingot and average area of macro-grain in this zone. Effect of structure refinement obtained by influence of electromagnetic field was...